[twobob]

I see you don't have a device yet... right? EDIT:.... oh... or perhaps you already have a 4

DEVICE: The k4 would have a inverted color set. so is possibly/probably not the right choice.. also you would need to run some extra code to manage the screen refresh which would extra pain/effort

I would choose: k3 (or dx for extra luxury, it would have slow screen refresh but meh more screen real-estate, it [the dx] also may need the extra refresh code I would have to check it has been a while...)

Personally I would: Just install the KUAL prerequisites bundle and KUAL itself.

IIRC there is an extension already (which needs a bit of config but meh it's doable even for an end user) EDIT: ah yeah HERE

Ubuntu is fine - (I use Ubuntu Mint so it would be much like my setup)

EXAMPLE: I use my k3 to monitor when I should get out of the bath by VNC'ing into my machine and watching the build's roll by.

CAVEAT: moving around on the screen is currently a bit of a PITA... no complete solution exists yet that I know of...
k3: You would be restricted to an 800x600 resolution. or 600x800
It may not work EXACTLY as you imagine it might. but input is supported and configurable

EXTRA TRICKINESS: The k4 does have an (extremely complicated) option of supporting OTG USB devices.. ( a mouse or an external keyboard) but that is still something that is on my TODO pile so I can't help you further there other than indicate it exists and point you to resources. Whether this would be extremely helpful I have no Idea... need more info and honestly I am just mentioning it here for completeness to the answer. EDIT: I note from your other posts around and about that this IS something that you are interested in... so might be worth the effort. But I cant help further with the final implementation. however there are all the modules you might need in the (as yet unreleased)kual-system project. But as I say... Can't guide you through that.

K3 solution ALTERNATIVES: There is a solution to setup the device as an EXTRA screen (IIRC, yeah.. I am sure... I did it once EDIT: okay here just read the whole thread) and that may be an option but extra effort and research/reading/resources will be required.

QUESTION: you say you are looking to "develop" on the device... In LaTex. What GUI do you use for that... or is it a text editor only job. I have no idea.

FINAL THOUGHTS: I would even be happy to quickly mock up a check to see how realistic/good the solution might be (with screenshots) given more info... but I need more info.

Hope that helps.